Thermodynamic and spectroscopic investigations of aluminas and thermodynamic studies of other solid systems

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:5701084

Healy, M H

This dissertation describes thermodynamic studies of the adsorption of a variety of liquid and gaseous bases on to a variety of solid acids, such as transition aluminas, a sulfonic acid resin (Dowex), graphite and anthracite coal. Fourier transform infrared spectroscopy studies were also conducted to identify the type, strength, and quantity of acid sites present on two transition aluminas, delta-theta and kappa. Heats of immersion of delta-theta and kappa aluminas into a variety of adsorbates of differing base strengths and geometries were obtained to quantify heterogeneous Lewis acid-base behavior. An in situ infrared spectroscopy investigation was conducted using four basic adsorbates to identify the acidic sites present on delta-theta and kappa aluminas. For two adsorbates, pyridine and 2,6-lutidine, adsorption studies were conducted between 298 and 983 K and at adsorbate pressures spanning from 1.33 Pascal (Pa) to 1.33 kPa. The adsorption of acetonitrile and n-butylamine was conducted at 298K using adsorbate pressures ranging from 0.66 Pa to 8.65 kPa. With all of the adsorbates a Lewis acid coordination site, designated as an outer or weaker site, and hydrogen-bonded complexes are identified. Broensted acid coordination is detected only when a strongly basic adsorbate, n-butylamine, is employed as the probe molecule. The strength of the sites, as quantified with pyridine is similar on both aluminas; however, with acetonitrile, a stronger coordination complex is formed on kappa alumina than on delta-theta alumina. The environment surrounding the acid site affects the adsorption of 2,6-lutidine; although it is a stronger base towards protonic acids than pyridine and might be expected to interact more strongly with alumina, only a weakly bound species is formed.

• Research Organization: Duke Univ., Durham, NC (USA)
• OSTI ID: 5701084
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600* -- Coal
Lignite
& Peat-- Properties & Composition
ACETONITRILE
ADSORPTION
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
AMINES
ANTHRACITE
AZINES
BLACK COAL
CARBON
CARBONACEOUS MATERIALS
CHALCOGENIDES
COAL
ELEMENTAL MINERALS
ELEMENTS
ENERGY SOURCES
FOSSIL FUELS
FOURIER TRANSFORMATION
FUELS
GRAPHITE
HETEROCYCLIC COMPOUNDS
INFRARED SPECTRA
INTEGRAL TRANSFORMATIONS
MATERIALS
MINERALS
NITRILES
NONMETALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PRESSURE DEPENDENCE
PYRIDINE
PYRIDINES
SORPTION
SORPTIVE PROPERTIES
SPECTRA
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES
TRANSFORMATIONS
WETTING HEAT